Motion translating device



Sept 16, 1952 B. H. SNOW 2,610,520

- MOTION TRANSLATING DEVICE Filed Sept. 6 1951 Barton H. 5n OW,

Wormw- His Attbr 'neg.

Patented Sept. 16, 1952 MOTION TRANSLATING DEVICE Barton H. Snow, Cincinnati. Ohio, assignor to General Electric Company, a corporation of New York Application'September 6, 1951 Serial No. 245,283

My invention relatesto devices for translating linear motion to rotary motion or .viceversa, and more particularly to devicesforjtranslating the rectangular components of motion'of a universally mounted lever or joy stick into rotary motion of a pair of shafts or the levers thereof.

A primary object of my. invention is to provide a new and improved device of the above sort. in which a planetary gear system is employed to accomplish the motion translation. 7

Another object of my invention is to provide such a device having a dependable neutral or null position.

A further object of my invention is to provide a very compact device of the above sort.

Still a further object of my invention is to provide such'a device whichis mechanically simple, easy to assemble, and inexpensive in cost.

In carrying out my invention in one form thereof, I provide amotion translating device having a casing'with end walls spaced apart in substantially parallel relation. A pair of concentric shafts are rotatably mounted in one end wall of the casing, and within'the casing a .pair of spur gears are secured on these shafts in axial spaced relation. each gear being secured on 'a separate shaft. Also positioned in substantially parallel spaced relationwithinthe casing are a pair of fixed ring gears,'and intermeshed each between one of the ringgears and one of the spur gears are a pair of planetary gears. Each of the planetary gears is coupled to be moved by an actuating member which is slidably mounted within the casing for universal planar movement. The respective couplings between the actuating 9 Claims. (o1. 74-47 The features of this invention which are believed to be novel and patentable are pointed out v; with particularity in theappended claims. The

invention itself, however, both as to organization and mode of operation, together with additional objects and advantages thereof may be best understood-by reference to the following description; to be'taken in-conjunction with the accompanying drawing in which:

Fig. 1 is a cross-sectional'view of amotion V translating device embodying my invention Fig. 2

member and the planetary gears are such that each gear is moved in response to a different rectangular component of movement of the actuating member, or vice versa, the actuating member is moved in mutually perpendicular directions Since the movement of either planetary gear causes a rotation of its associated spurgear and thus of the associated shaft, or conversely the rotation of either shaft causes a movement of the associated planetarygear, the rotation ofthe shafts are thus'caused by or are the cause of separate rectangular components of the movemo tion-to rotary motion, or vice versa. a lever is mounted in-the other end wall of the casing for universal; movement and is connected to the j actuating member. I

"in response to movements of the planetary gears.

is a view in partial section taken on the line 2-2 of Fig. 1; Fig. 3 is a sectional view taken onthe line 3-3 of Fig. 2; Fig. 4 is a fragmentary crosssectional; view taken on the line 4-4 of Fig. 1; Fig. 5 is a fragmentary cross-sectional view taken on the line,5 5 of Fig. 1; and Fig. 6 is an exploded perspective view of a motion translating devicesimilar in principle to that shown at Figs.

Referring to Fig. 1, I have shown therein a motion translating device having a casing formed of a plurality of annular members which are secured by bolts I and pins la between a cup-' shaped end wall 2 and a fiat closure plate 3.

Thecasing also includes an interior dividing wall A. whichseparates end wall 2 from the various annular members. These annular members actually comprise a pair of gear rings 5 and 6 whose teeth extend inwardly toward the center of the casing, and a pair of spacing rings 1 and 8 which respectively provide clearance between the gear rings and between the lower gear ring and plate 3. In other words, the gear rings 5 and 6 are mounted in substantially parallel or axial spaced relation between dividing wall or plate 4 and closure or base plate 3.

The closure plate 3'is provided with an aperture 9 ,atits center point and extending through this aperture are a pair of concentric shafts l0 and I I. The outer shaft It has a toothed flange or spur gear l2 formed at its upper end within the casing and mounted on inner shaft ll between gear l-'2 and plate 4 isa spur gear l3 In other words, gears l2 and l3 are separately mounted on shafts l0 and l l in axial-spaced relation to each other. r

Spur gears l2 and iii are so mounted that gear 12 lies in the principal plane of ring gear 6 whereas spur gear I3 lies in the principal plane of ring gear 5. Between the spur and ringgears lying in the same plane there are positioned-intermeshing planetary gears l4 and [5, gear Hi being in engagement with ring gear 5 and spur gear I3 and gear l5 being inengagement with ring gear 6 merit in one direction only.

3 and spur gear 12. A guide member I6 is positioned between gear 15 and dividing plate 4 to prevent cocking and jamming of gear I5 against base plate 3. Guide member [5 is secured to plate 4 by a pair of screws l1 and has a bifurcated portion accommodating a vertically extending pin G3 which is'mounted at its lower end in gear 15. As shown, pin l8 extends upwardly from gear through an arcuate slot it in plate l into a groove 29 formed in the lower surface of a slid-- able coupling member'or plate 21 which is positioned above plate 4. Member or plate 21 is slidably movable with respect to plate 4 and provided on its lower surface with a radiallyext'ending key 22 which fits into a lreyway 23 formed in the upper surface of plate ,4. The

that each of the spur gears and thus each of the shafts l6 and H are rotatedin response to a separate rectangular component of the movement of plate 26 or conversely rotation of'either of the shafts causes a different rectangular movement of plate 26. a

In order to provide-input or output means do pending'upcn whether the device is to be em ployed to translate linear .motion to rotary motion, or vice versa, a universally mounted lever or joy stick 3i is connected to member 25. More specifically, lever 31 is provided with a pair of spherical journals 32 and 33 which are interaction of key 22 with keyway 23 permits,

movement of plate 21 in one direction only, i. e;,

in the direction of the key and the groove. Plate 2! is; thusm'o'unted in the casing for linear move- ;On its upper surface member il i's'provided vitlria key 24 which extends at right angles to the key 22 and fits into a keyway 25 formed in the lower surface of an actuating member 2% which'is positioned betweenme'mber 2! and end wall 2 of the casing. Member "26 is'slidablyinovable onmember 2 i but the interaction of key 24 and lieyway 2 5 limits themo'tion of member 2% relative to member 2! to one direction only, the direction of key E i and keyway 213. However, sincemember 24 may move in a direction perpendicular to keyM, member- 28 may alsomove inthat direction. "Thus by moving relative to member 2! in one direction and by moving-with member 2 l in the'directi'on perpendicular thereto,

member 2}} may move inany direction in the plane perpendicular to the planes of section of Figs. 1 and 3. In other words, member 26 is mounted within the casing for universal planar movement.

Besides rey'way 25, member 2% also has formed in itslower surface a groove v2'! which extends atrightanglesto lreyway 25. This groove 27 accommodates'the upper end of a vertically-extending pin 28 which at itslower end is secured to the planetarygear-Hi. Intermediate member 28 "and gear M the pin extends through an arcuate slot 29 in plate l and a substantially segmental recess. 30 in member 2-H.

As is shown in Fig. 1 the groove 27 extends in the same direction as the key 22 formed on the lower surface of member 2! and thus 'pin 23 is moved by the walls of groove 2'! only when member '26 is moved relative to member 2i. Alternatively stated, pin 28 is moved only when the movement of member 2% contains a component perpendicularto groove 27 and key 22. Thus pin 28 is moved by a component of movement'of plate 25 perpendicular to the component of movement which causes a movement of plate 2! and thus of pin it. In other words, pins 23 and I8 are moved in response to separatcperpendicu- 'lar or rectangular components of movement of r 33 and 35 to form ball or universal pivots. Bearing 34 is fixedly mounted in casing member 2 while bearing 35 is similarly mounted in actuating member 26.

The manner in which the right angle compomerits of movement of lever E-lare translated to rotary. motion-of the output shafts it and -l l, or vice-verse, may b'ebestiunderstood by: reference to Fig. 6 which is an exploded-view in perspective of a motion translating-device having various members identical in function with those of the device shown in Figs; l=-5 but slightly. d-ifierent in form-for clarity of. illustration. :The'yarieus parts ofthe device ofFigrG are designated'by thesame reference numerals as'the corresponding parts of the device ofFigs. 1 :5. in Fig; 6 the device is shown as controlling the "outputs ofa pair of conventional selsyn generators 38 and 31, the rotor 38 of generator 36 being coupled to shaft ill and the rot-ores ofgenerator 37 being coupled toshaftllif'":

First, assumingthat the motioncflever 31 is as indicated by the dotted lines in Fig." 1, i. e. is in the plane of section of Fig. i, then plate 25 is slidably moved in the line of direction of groove 21 and thereby at rig-ht angles to the-line of directionof keyway 25. This movement does not afiect pin 28, but merely changes its-position within groove 21. Howeven-due to theengagement of key 2'2 with keyway-ZE, such a-movement of plate tt doesresult in a similar movement or plate 2|. As .plate 2! movesalong with key 22 riding in kayway 23,.pin iB-is also-moved in thersameclirem tion by, groove '28, seas to effect a movement of planetary gear l3. Gear [5-, of course, because of its engagementwith both ring gear 6 and spur gear l2, cannot move in a straight line but must necessarily move in angarcuate-path. Thus, the unidirectional'force applied to pin-l8 from groove 2%! results in gear "I 5 moving in an arcuate path,

as-is illustrated by the dottedli-nes in Fig. 5

of rotation of gear 15 and thus upon-the direction direction. of rotation of shaft it depends upon in which direction lever 3! is moved in, the-plane of to which it is connected. As is well known in the a art, such a movement'of a planetary gear between section of Fig. 1. Similarly, the angular displace *ment of shaft ID is dependent upon themagnitude of displacement of lever 3 l', Thus the angular' displacement of shaft ill-froma predeter- 1 mined neutral position'is dependent in magnitude and direction upon themagnitude anddirection movement of pin 18 While spur-gear ['3 is rotated" of the displacement of lever -3l fronr-the illustrated null position of Figs. 1-5, the displaceand move with plate 2|.

ment of lever 3|, of course, being in the plane of section of Fig. 1.

Now, assume the movement of lever 3| to be at right angles to the above movement, 1. e. to be in the plane of section of Fig. 3, so that it causesa movement of plate 26 also at right angles to the above movement. This. movement, since it is at right angles to the line of direction of. groove 21, causes a movement of pin 28; but since it is in the line of direction of keyway 25 and the engaging key 24, it does not cause any movement of plate 2|. Even if there were sufficient friction between the plates to cause movement of plate'2|,.the engagement of key 22 with the keyway 23 in dividing wall 4 would prevent movement of plate 2|.

Y The unidirectional force applied to'pin 28 tends toqmove planetary gear M in astraight line. However; since it engages both gears 5 and I3, gear |;4. can move only in an arcuate pathas illustrated in Fig. '4. Therefore, the force applied to pin 28 results in an arcuate movement of both gear i4 and pin28. Its engagement with ring gear 5 causes gear I4 to rotate while following this arcuate path, and its rotation-in .turn causes rotation of gear l3. Since gear I3 is mounted on output shaft movement of gear I Hi thus results in 'a rotation of shaft I I.

The direction of rotation of shaft depends upon the direction of rotation of gear l4 and thus upon the direction'of movement of pin 28 as actuated by lever'3l through plate 26. Thus movement of lever 3| in one direction in the plane of section of. Fig, 3 causes angular displacement of shaft II in one direction while an opposite movement of lever 3| causes an angulardisplacemnet of shaft H in the opposite direction, the magnitude of angular'displacement in'either case being dependent upon the magnitude of lever movement. The return of lever 3| to the illustrated null position from displacement in either direction therefrom returns shaft to'a predetermined neutral position.

Thus far, it'has been shown that "shafts l6 and Hare turned respectively in response to movements of lever 3| in'a pair of planes lying at right angles to each other. However, lever 3|, since it is mounted in universal pivots, may also be moved in planes intermediate these rectangular planes to cause simultaneous displacement of both shafts. Any such movement of lever3| and thus of plate 26 causes simultaneous movement of both pins |8 and 28 and thereby a simultaneous movement of gears l4 and I5.

For example, assume lever 3| to be moved from its null position in any plane displaced from the aforesaid rectangular planes. is attached to lever 3|,-must also move in the 'same direction, but'in order for it to'do so a Since plate 26 can move with respect to plate 2| in-one direction only while plate 2| can move only at right angles to that direction, a movement of both plates is obviously required to accomplish a movement of plate 26 in a direction lying intermediate the rectangular directions. In other words, plate 26 must not only move with respect to plate 2| but must also actuate Thus, the movement of lever 3| is, in effect, broken down into two right angle or rectangular components, the displacement of plate 26 with respect to plate 2| being indicative of the size of one component and the displacement of plate 2| itself being indicativepfthe size of the other'component.

Plate 26, since it For movement of lever 3| in a plane displaced 11. degrees from the plane of section of Fig. l, i. e. for a movement of plate 26 in a direction displaced 12 degrees therefrom, the movement of plate 2| is equal to the cosine of 11. degrees times the total movement of plate 26 and the movement of plate 26 with respect to plate 2| is equal tothe sine of n degrees times its total movement. Of course, the direction of movement of pltaes2e and 2| depends upon the directionof movement of lever 3| in the aforesaid plane. As before, the movement of plate 2| causes a movement of pin |8 resulting in a rotation of shaft l6 whereas the movement of plate 26 with respect to plate 2| causes amovement of pin 28 resulting in a rotation of shaft II, the direction of rotation in either case depending upon the direction of movement of the associated pin.

Thus, shaft I6 is displaced in response to the movementof lever 3| in a predetermined direction from its null position or to any component of lever movement lying in that direction, whereas shaft is displaced in response to lever movement or any component thereof lying at right angles to the above predetermined direction. In other words, a displacement of rotor 38 from the illustrated null position is dependent upon one rectangular component of movement of lever 3|, while a displacement of rotor 39 is dependent upon the other rectangular component of movement. This permits the use of generators 36 and 31 as the actuating means in two electrical circuits for energizing various positioning means, such as servo devices, in response to the rectangular components of lever movement. For example, these generators could be very advantageously used as the actuating means in the aileron and elevator channels of the-maneuvering control system of an autopilot.

1 Ihave described the operation of the illustrated device with reference to applications in which rotary movement of a pair of output shafts is desired in response to a linear movement of an actuating lever or joy stick. However, it should be obvious that it is also possible by means of my invention to obtain a linear movement of a universally mounted lever in response to a rotational input on a. pair of rotatable shafts; for example, the illustrated embodiment may be run backwards.

Further it should be understood that among the modifications of the illustrated device, I contemplate a device in which the coupling member 2| is omitted. In such a device both planetary gears would be. coupled directly to the actuatingmember 26, each to be moved in response to a separate rectangular component of its planar movement. An example of suitable coupling means would be pins mounted at their one ends on the planetary gears and extending at their other ends into mutually perpendicular grooves formed on the single actuating member.

Thus, while in accordance with the patent statutes, I have described what at present is considered to be the preferred embodiment of my invention, it will be obvious to those skilled in the art that numerous alterations and modifications may be made therein without departing from the invention, and I, therefore, aim in the appended claims to cover all such alterations and modifications as fall within the true spirit and scope of this invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

l. A motion translating device comprising a housing; having spaced apart end walls, a'pair' of ring gears fixedly mounted in substantially parallel spaced relation in said. housing, a pair of concentric shafts rotatably mounted on one of said end walls, a pair of spur gears separately mounted on said shafts in axial spaced relation within said housing, a pair of planetary gears each mounted in intermesh-ing relation with one of said ring gears and one of said Spur-gears, an actuating member slidably mounted in said housing for universal planar movement, coupling means; connecting said actuating member selectively to move one of said planetary gears in one direction and to move the other of said planetary gears in a direction, perpendicular to said one direction, and a lever pivotallymountedqon said within said housing eachjin intermeshing rel-a-.

tion between one of said spur gears and one of said ring gears, an actuating member sl dably mounted in said housin for universal planar movement, coupling means connecting said actu- V ating member selectively to move one of said planetary gears in one direction and to move the other of said planetary gears inadirection perpendijcular to said one direction, and a lever pivotally, mounted on said housing for universal movement and: connected to said actuating member. V

3. A motion translating device comprising; a housing having spaced apart end walls, a pair-oi ring gears fixedly mounted in substantial-Hyperallel spaced relationin said housing", a pair of concentric shafts rotatably mounted on one of said end walls, a pair of spur gears separately mounted on sai'dshafts in spaced axial' rela -"on within said housing, a pal of planetary gears eaclrmcunted' in intermesh relation with one of said ring gears and one or aid spur: gears, an actuating member slidably mounted in saidhousing for universal planar movement, and coupling means connectin said actuating member selec= tively to move one of said planetary gears; in one direction and to move the other-of said; planetary gears in a direction.perpcndicularto saidone directi'on.v

4. A. motion translating device comprising a housing, a pair of ring gears fixedly mounted in said housing, a pair of shaftsrotatab'ly mounted on and extending into said housing, a pair of spur gears each mounted on one of. said shafts within said housing apair of planetary gears mounted within said housing each in intermesh-- ing relation between one. of said spur-gears and one of said ring gears, an actuating memberslidably mounted in said housing for universal pla= nar movement, and coupling means connecting said actuating member selectively to move one of said planetary gears in one direction and to move the other of said planetary gears in a direction perpendicular to. said one direction.

5. A motion translating device comprising a housing, a pair of ring gears fixedly mounted within said housing, a pair oi shafts rotatably mounted on and extending into said" housing, a pair of spur gears each mounted on one of said shafts, within said housing, a pairoiplanetary gears mounted in said housing each inintermeshing relation between one of said; spur gears and one of said ring gears, a coupling member slidably mounted'within said housing for linear movement in one direction, first coupling means connecting saidcoupling member to one said planetary gean'an actuating member mounted in said housing for universal planar movement, second couplingmeans connecting said actuating member to said first coupling member for movement in said one direction, third coupling means connecting said actuating member tomove with the other oi said planetary gears. in a direction perpendicular to said one "direction, and a. lever pivotally mounted on said housin for universal movement and connected to said actuating memher.

6. A motion translating devicecomprising a casing having spaced apart end walls, a pair of ring gears fixedlymounted in substantially parallel spaced relation in said casing, a pair of concentric shafts rotatably mounted in onev of said end walls, a pair of spur gears separately mounted on said shafts in spaced apart relation within said casing, a pair of planetary gears each 'mounted. in. intermeshing relation with a diiierent one. of said spur gears and a different one of: said ring ears; a coupling member slidably mounted in said casing for linear movement in one. directionand provided with a groove extending perpendicular to said one direction, an actuating member slid'ably mounted in said casing for universal planar movement: and. provided with a groove extending in. said one. direction, a pair of pins each .mounted on one of saidplanetary gears and. each extending into one; of. said grooves, key means; connecting said actuating member to move with said. coupling member in. said one direction, and a lever pivot.- ally mounted in the. other wall: of said, housing for: universal movement and connected to said actuating member;

'7'. A motion translating device comprising a housing having spaced-apartend. walls in. substantially parallel spaced relation, a. pair of fixed, ring gears mounted. in said housing in substantially; parallel spaced. relation. between said walls, a, pair, of concentric shafts rotatably mountedi-n, one of. said walls, a pair of spur gears separately mounted on said shafts: within said housing-in axial spaced relation, a pair of planetary gears; mounted in said, housing each in intermeshing relation between one, of said spur; gears and one of said ring gears, acoupling member slidably mounted within, said housing for linear movement in one. direction, first coupling means connecting said coupling member to one of; said planetary gears, an actuatingmember slidably mounted in said housing for universal planar movement, second coupling means connec; .ig said actuating: member to movesaid-couplin member; in said one direction, third coumeans connecting said actuating member to move: theotherof said planetary gears in a directionv perpendicular to said, one direction, and a. lever.- pivotally mounted? in the other wall of said. housingv for universal movement and connected, to. said actuating member...

8; A motion translating device comprising: a housing; a platemember fixedly mounted within saidhousing, a pair of ring gears fixedly mounted within said housing, a pair of shafts rotatably mounted onand extending into said housing, a pair of spur gears each mounted on oneof said shafts "within said housing, a pairof planetary gears mounte'd' in said housing each: in' intermeshing relation between one of said spur gears and one of said ring gears, a coupling member slidably mounted in said housing, key means connecting said plate member and said coupling member to limit the movement of said coupling member to:linear movement in one direction, first coupling means connecting said coupling member to one said planetary gear, an actuating member mounted on said housing for universal planar movement, second coupling means connecting said actuating member to move with said coupling member in said one" direction, third coupling means connecting said actuating member to move with the other said planetary gear in a direction perpendicular to said one direction, and a lever pivotally mounted-on said housing for universal movement and connected to said actuating member.

9. A motion translating device comprising a housing having spaced apart end walls, a fixed member mounted in said housing intermediate said end walls, a pair of ring gears fixedly mounted in substantially parallel spaced relation in said housing, a pair of concentric shafts rotatably 10 a mounted on one of said end walls, a pair of spur gears separately mounted on said shafts in spaced axial relation within said housing, a pair of planetary gears each mounted in intermeshing relation with one of said ring gears and one of said spur gears, a coupling member slidably mounted insaid casing, key means connecting said fixed member, and said coupling member to limit the movement of said coupling member to linear movement in one direction, first coupling means connecting said coupling member to one said planetary gear, an, actuating member slidably mounted in said casing for universal planar movement, key means connecting said actuating member to move with said coupling member in said one direction, second coupling means connecting said actuating member to move with the other said planetary gear in a direction perpendicularjto said one direction, and a lever pivotally mounted on said housing for universal movement and connected to said actuating member.

BARTON H. SNOW.

No references cited. 

